This invention relates to a multi-spindle fastening apparatus having a fastening head which is used for performing simultaneous fastening operations to a workpiece having plural portions to be fastened, and is more particularly directed to such an apparatus having plural replaceable heads wherein a selected one of the plural heads is replaceable with another in compliance with a change in kind or type of workpiece.
An apparatus of this kind has been known wherein a head is detachably provided on a machine base so that the head can be manually detached therefrom and/or replaced with another as an occasion demands. Further, another apparatus is known wherein plural heads are fixedly disposed on a machine base and the workpiece is supplied to one of the plural working stations below a corresponding one of the heads. However, the former machine has the disadvantage that it is troublesome to replace the heads, and the latter machine has the disadvantage that it is necessary for each head to have an independent working station supplied with the respective workpiece of a different kind to be worked on by that particular head. Consequently, a large space for installation of those stations is required.